Lion Heart
by inkbender
Summary: When the boy who'd only wanted to see the worlds outside the Walls is thrown into a completely different universe with his home world destroyed by Darkness, he must use his determination with the help of a certain lion-hearted mentor and the power of Light to find his friends and return home again. Shingeki no Kyojin a la Kingdom Hearts style with a twist.


Creeping shadows with haunting yellow eyes slid out from the dark places of the house.

Eren dropped the bowl of soup he was holding. "Mom?"

His mother choked and drew near to him, grabbing his shoulders. "Eren…" she said slowly. "Go find Armin."

The shadows moved, sliding along the ground, tiny little hands reaching for him and his mother

(_Only little rabbits are afraid of the dark_)

(_I wasn't afraid of the dark, Levi, but I am now_)

"Mom, what are they?" He couldn't stop his voice from trembling as his mother slowly guided him towards the front door.

"Honey, Armin's parents will know what to do," she said, with such assurance in her voice that Eren obeyed right away—until the shadows attacked.

He spun around on his heel and bolted straight for her as she stumbled forward with the extra weight of three little monsters on her back, but her screamed command froze him in his tracks. "Eren! Listen to me for once and find Armin now!"

"But—"

His mother screamed one final time, a wail of agony as one of the creatures shoved its claws through her back. Just like that, his mother dissolved into black mist. A lonely red heart drifted upwards out of the haze where his mother had once stood. It glittered and spun and phased through the ceiling and out of sight.

(…_Mom?_)

When the tiny little shadows turned their unblinking yellow eyes upon him, Eren's feelings of anguish and loss quickly transformed into pure hatred. He grabbed the nearest object he could use as a weapon—the broom his mother had used just yesterday to sweep up an empty pitcher. And there was the shattered bowl of soup he had dropped, and his mother would have used the mop to clean up the spilled liquid…

Mom…

He roared as he sprinted towards the things that killed his family. He and Levi had practiced sword-fighting with mops and brooms before, and though the antics had started out harmless and playful, more recently their sparring sessions had gotten quite violent and aggressive.

(_You're too weak, Eren_)

(_Levi, you're the one who's fighting too hard_)

(_Nonsense, you've just got to strengthen your heart_)

Eren used the broom's blunt end to swat the little monsters into the walls and floors—but they kept coming, more and more of them, and the broom didn't even seem to hurt them one bit.

(_I'm not running away, Mom, I'm not going to abandon you like dad did_)

Yet that was exactly what his mother had wanted him to do. It was her last wish... and the way she had said it had almost sounded like a solution.

(_Find Armin's parents they'll know what to do_)

Armin's parents were scientists, right? They knew a lot. Armin knew a lot. They'd know what to do. Maybe they could bring his mother back! Disappearing into dust definitely wasn't a normal way to die—maybe it wasn't even dying. (Though there was a certain sense of finality in the way that pink heart had disappeared into the sky, Eren's irrational mind chooses to ignore this.) Whatever the reason, he just had to get to Armin.

He wiped tears from his eyes as he ran out of the house, leaving the invisible ashes of his mother in the shadow-infested house behind him. He barely noticed that all around him, people disappeared in explosions of dark mist: sometimes with only glittering red hearts left behind to prove that they'd existed, and other times with new insect-like ghosts with unblinking yellow eyes and quivering antennae appearing in their place. Chunks of debris and entire houses levitated slowly into the storm above. It felt like Shiganshina, his home of twelve years and the only world he'd ever known, was literally being torn apart piece by piece.

Half of Armin's house was already rising into the air when he arrived; the half that remained on the ground was full of squirming, black, little monsters. "Armin!" he shouted, but there was no reply. With no other place of security left, Eren ran for the only other location of comfort he knew.

He, Levi, and Armin. They had spent so many years by the abandoned wishing well, reading one of the books that Armin had stolen from his father's study. They'd huddle around the well and learned all about lands of ice floating in infinite salty lakes, of fiery water that exploded out of the tops of mountains, of grasslands with strange creatures, and together, the three of them had sworn that they would escape the Walls and explore those new worlds out there. Whenever he, Levi, and Armin had met at the wishing well, they'd wanted nothing more than to leave their world behind. Funny how, now that his world was literally falling apart, Eren wanted nothing more than to return to that time of an hour past, when things were normal and bright and unbroken and his mother remained at home and his father…

(_Dad…_)

He ran into the abandoned courtyard minutes later. Even now, nobody bothered to go there—except for Levi, who had one hand braced against the well's surrounding wall, his back facing Eren. His feet and legs disappeared into a small whirlpool of shadowy vapor.

"Levi!" Eren cried out in panic.

His best friend turned just his head to look at Eren over his shoulder. "What is it… Eren?"

"Your feet! Move, idiot!"

"The wishing well," Levi said calmly, remaining in place. "We should have known. It's our way out."

"You're not making any sense!" Eren sprinted over and grabbed Levi's arm and tried to yank him out of the creepy black mist—but it was like his feet were glued to the misty darkness below him, and Eren realized with horror that Levi was _sinking_, disappearing slowly into the solid shadows.

"Com'on, Eren," Levi smiled. "You, me, and Armin: we wanted to go outside the walls, didn't we?"

Eren glanced upward, past the roofs of the houses, up at the gigantic walls that trapped humankind within a gigantic cage—and his mouth dropped. The walls were no longer there; instead, there was only a solid purple darkness that just seemed to suck up debris—parts of houses, stonework, horses, trees, people.

Levi's hand tightened around his. "Let's go outside the walls," the other boy said, pulling him downwards.

"No!" Eren yelled, trying to pull away, begging Levi to let go of him. "My… my mom… I have to find Armin!"

Levi's sharp blue eyes glinted in the darkness, but for a second, they seemed to flash a haunting yellow as the swirling darkness beneath him reached up with tendrils of black smoke to drag both him and Eren under.

(_Levi, I'm afraid of the dark now_)

(_Don't be_)

Light exploded in front of Eren's eyes, knocking him away. He landed on the ground in front of the wishing well and could only watch as Levi's hand sunk into black smoke

(_Just like Mom_)

and disappeared.

His entire world shattered. Not just his mind—the loss of everybody he'd loved in such a short amount of time—but his world within the walls dissolved into black matter. The ground beneath him yawned open and Eren tumbled into the darkness, but he never hit the bottom—he just kept falling and falling. His eyes saw strange visions of his father, tears in his eyes as he came towards his own son with a needle and syringe in hand. He saw Armin's father in his study, poring over stacks of books and research, before Armin's mother rushed him away. Armin brought him the book he stole, his eyes shining with excitement and wonder. The sweat that dripped down Levi's brow as they sparred together, wooden handles clashing against each other, or tearing across the other's soft flesh, leaving bloody wounds. His mother carefully bandaging up his injuries, and her loving smile, and the haunted look in her eyes as she turned away.

(_Mom don't leave me Armin where are you Levi don't leave me here alone_)

Darkness.

But in the darkness, light flickered to life in the form of a strange key. Even though he felt as if his entire body was dissolving away into endless darkness and insubstantial mist, he reached forward. Eren Yeager, the boy who, even though he was scared, possessed an incredible determination, reached towards the shining key with everything he was… and grabbed the handle.

The resulting flash of light had blinded him and overwhelmed his mind, robbing him of consciousness.

* * *

(_You, me, and Levi: we're going to break free of these walls_)

(_The worlds are endless out there, and they're just waiting for us to explore them, Eren_)

(_Creeping shadows_)

(_You've got a rabbit heart, Eren_)

Eren jerked awake with a shock, breathing hard. Rocks dug into his butt. Sensation. He still had sensation. Sight. He glanced around, taking in the stonework of the wall in front of him.

And that's when he noticed his first difference: red. The stonework was red. They weren't the cut grey blocks of his hometown. The houses around him were neat and civilized. Light spilled into his dark alleyway from a tall metal pole with a bright white light atop it that did not give off the comforting flicker of normal orange flames.

This was not his world.

He scrambled to his feet. The alleyway emptied out into a courtyard that appeared to be a mix between an old castle and a festive carnival, with bright, gaudy lights suspended among gray buildings. It was a bright and colorful city… the only thing missing were the people.

"Hello?" he called out into the empty space. "Armin? Are you here?"

Underneath the multicolored lights, the shadows shifted.

They didn't have mouths. They only had unblinking yellow eyes (_yellow like Levi's_) and twitching antennae and their claws left stinging scratches on his back and legs as he ran like a coward, ran and ran until he came upon a tall wooden door that wouldn't budge no matter how much he yelled and threw his tiny body against it and pounded against its splintered surface.

He could no longer run.

He had to fight.

(_I don't want to fight, Levi, _his eleven year old self had said_. I'm too tired._)

(Levi had bopped him on the head with his mop._ Com'on, just fight me. I'll even give you the rake._)

(_That rake hurts. I don't want to hurt you._)

(_You can't give up without trying. You die if you don't fight. Don't be a loser, Eren._)

(_I'm not a loser! I just don't want—_)

(Levi whacked him in the face this time, though only with the dirty strands of the mop._ Fight me, Eren. If you win, you live, and if you lose, you die; but if you don't fight, then you can never win!_)

He had to fight. Fight and win and live and find Levi and Armin and go back home, if home even existed anymore. He balled up his fists, concentrating on the shadowy ghosts in front of him. He had nothing that he could use as a weapon, but he could use his own body to strike them aside…

And with a flash of light, the gigantic key that had saved him from eternal darkness and brought him here, appeared in his hands. For just a second, Eren could only stare in shock at the thing—but then the shadows leapt at him, their claws extended, and Eren acted on instinct. He swung the gigantic key at the little monsters, intending to only bat them to the side and run past them—but, seemingly on contact, the sinister creatures dissolved into mist when the key hit them. Within a minute, Eren had cleared the courtyard of the dark threats.

Eren could only stare down at the weapon that had appeared out of nowhere in a flash of light. The light had saved him when his world had been shattered into pieces and he was about to be enveloped by the darkness that had eaten away at everything else. But what about even earlier than that? There had been an explosion of light that had knocked him away from Levi; had that also been the key's doing?

What was this weapon? Was the reason why it seemed to be able to defeat the monsters of darkness was because it seemed to be made out of light? Where had it come from, and where had it taken him?

(_Shadows melting out of the dark places of his house and coming for him and his mother_)

Was this town overtaken too?

Could he fight back with this key?

Could he win?

As he ran about the courtyard, searching for an exit other than the locked wooden door, more monsters rose to greet him, appearing out of the shadows cast by twinkling lights of color. Without hesitation, Eren dove towards them with his key-like weapon, smashing them into little clouds of black mist. But the more he fought, the more they just kept coming, more and more of them appearing from underneath park benches, from behind stone walls and building shadows, yellow eyes seeking him out hungrily…

A ring of fire spontaneously roared to life around him, trapping him in a tiny bubble of heat. Before Eren could even comprehend what was happening, the fire exploded outwards, its sizzling light vanquishing all the little shadows around Eren.

"They'll keep coming at you out of nowhere."

Eren's head snapped in the direction of the feminine voice to his right, but he couldn't see anyone—not until the person jumped down from the top of a building, landing on the roof of a shorter building within his eyesight.

The girl wore a white hoodie underneath a short, light brown leather jacket and form-fitting white pants covered up to the knee with sleek leather boots. A dark brown sash was wrapped around her waist while her entire body was criss-crossed with thin straps and belts of dark leather that formed a sort of full-body harness. The dulled brown of her outfit made her blonde hair that much more brilliant, and her ice blue eyes that much more piercing.

Her uniform was a welcome sight in a strange world, because it was the uniform of his homeworld's military. The only difference was that the badges on her shoulders and front left pocket did not bear the crossed swords of the trainees, the black and white wings of the Scouting Legion, the twin roses of the Guardian Corps, or the unicorn of the Military Police. Instead, her badge displayed a proud lion's head.

"Do you come from Wall Sina?" he called. He couldn't exactly tell from this distance, but the girl seemed _tiny_—especially with the gigantic sheath strapped to her left side. He could just barely see a pair of small silver wings on the hilt of the blade protruding out the sheath's end, but even that seemed much too large for the girl's small hands.

Her face showed little emotion; she only stared at him, her bright blue eyes almost looking straight into his soul. It was almost frightening—but at the same time, Eren couldn't help but feel relief that he wasn't the only person in this strange world. After encountering shadows since the moment he mysteriously arrived, Eren was thankful that he wasn't alone.

The girl finally spoke again, lifting an arm to point at Eren. "Those shadows will keep attacking you, as long as you wield that Keyblade."

Eren's eyes immediately landed upon his new weapon. The key of light that had saved him from the shadowy haze that had consumed Levi and brought him out of the darkness that had destroyed his world… it was called the Keyblade. He raised his eyes to the blonde girl and asked, "Do you know what happened to our world? And what do you know about this… Keyblade?"

The girl ignored him, looking away. "But why?" she murmured to herself. "Why would it choose a kid like him?"

"Hey! I can hear you!"

"Right," the girl said, snapping her attention back to him. "Hand that Keyblade over now, won't you."

It wasn't even a question; it was a demand, and it automatically riled on Eren's nerves. "Why don't you answer my questions first?" he snarled. "You're wearing the military uniform, I know it! I've memorized all the different sections of the military, and I'm going to join the Scouting Legion because—"

(_because I wanted to see the worlds out there, and look where I am now_)

(_I'd wanted to do it with Armin and Levi at my side_)

(_and I'd also expected my mother to always be there behind me, waiting at home_)

"We don't have time," the blonde girl said flatly. "Give me the Keyblade and I'll take you somewhere safe."

(_safety_)

(_what about this girl implies anything about safety? You really are just a little rabbit_)

Eren's grip tightened around the handle of the Keyblade. "Even if your clothes make you look like a honorable soldier from my world's military, you haven't given me any reason to trust you. At all."

Eren couldn't exactly tell, but it seemed as if the barest hint of a smile ghosted her lips then. "Alright. Have it your way then."

She placed one hand on the silver-winged handle of her blade and, without any visible sort of effort, unsheathed a gigantic ice-blue blade that exceeded the length of her entire body. Eren barely prevented his mouth from dropping open as the blonde carelessly slung the blade over one shoulder, bent her knees, and rocketed into the air, soaring above Eren's head carelessly to land on the other side of the courtyard.

This wasn't possible. She was too small. She shouldn't be able to jump that entire distance. And her blade was too large. He could now see that the blade's handle resembled the grip of a gun much more than the hilt of a sword, and that the grip even had a _trigger_. A tube also extended out of the butt of the gun-blade hybrid and disappeared underneath the brown sash she wore around her waist. It resembled yet looked nothing like the weaponry of the military.

"Last chance," the girl states flatly, the sword still carelessly slung over her shoulder.

Eren abandoned all rational thought as he growled, "Like hell," and rushed at her. He didn't underestimate her either; she might just be a girl, but, unless there was some weird voodoo magic at work that allowed her to easily hold a blade taller than she was, this blonde girl was ridiculously strong.

(_Come at me with that rake, Eren. Fight and live!_)

She dodged. It was so simple too; she simply stepped to the side, twisting her body to avoid his slash. She kept turning as he stumbled by, bringing up her foot as she whirled around to round-kick him in the back. It obviously wasn't met to hurt; it just knocked him off balance, and he barely caught himself.

(_She's not even using her weapon she's toying with me_)

Eren grit his teeth and charged at her again—but this time, he changed directions on her at the last minute. Fortuitously, it happened to be in the same direction that she dodged in, but again, she merely added another little hop into her step and bounced just out of reach. Her cool blue eyes tracked his every movement, never leaving the movements of his body.

"Stop playing and fight me!" Eren yelled.

The girl wordlessly held out the flat of her hand in reply, and Eren's eyes bulged as tiny flames whirled to life above her palm. It quickly expanded before exploding at him like a bullet from a military firearm, its huge bulk racing at him like a thrown ball.

Eren readied his Keyblade, waiting for just the right moment—and then he swung, batting the fireball away. The projectile hit the side of his Keyblade with a loud clang and a flash of heat before bouncing off, flying to the side and exploding upon impact with a stone wall.

He'd reflected fire.

No, first, the girl had _made _fire. Had she been the one to burn away all those shadows that had been mobbing him earlier? Was that a reason why he could trust her?

Eren had barely recovered from the supernatural attack before finding the girl right in front of him, her gunblade held offensively in front of her body, her long blonde bangs hiding her eyes but revealing the tiniest of smiles on her thin lips.

(_Levi had done this before, throwing a handful of dirt at him as a distraction before coming in with a surprise strike_)

He tried to cross the weapon in front of his torso to block her, but the girl was already too close and in the middle of her attack. She slashed once, the brilliant blue of her blade screeching against the thin silver of his before the pure force of the blow sent him flying backwards. She rushed him then, using the flat of her gunblade to send him flying even further, much like he had batted her fireball away.

He hit the ground, lost his balance, and tumbled haphazardly to a stop. Panting, he glared at his attacker from his prone position.

"You're not a fighter," the girl said. "You won't stand a chance out there. Those little shadows? They're small fry. There are worse things out there, and they will not hesitate to kill you."

"Why are you doing this?"

"Me?" the girl's blue eyes unexpectedly widened innocently, her face morphing into an expression of concern so fake that it made Eren sick. "Why do you think a girl as little and weak as me would try to fight somebody like you?"

(_Armin's blue eyes wide open, young and innocent, using his mind and his words to manipulate people's emotions and thoughts because he was too weak to fight with his fists_)

Eren's eyes snapped angrily as he rushed forward, his hands gripped tightly around the Keyblade. Just like trying to overwhelm Levi with multiple little strikes, he brought in his weapon from several different directions, trying to find open or weak spots, smashing against the girl's blue guard. His blows became stronger and faster as he jabbed and slashed and countered with all his might, forcing his opponent back one step, two steps…

The girl's faint smile was drowned out by a flash of blue light.

He was somersaulting through the air in confusion, unsure of how he got in that position. His body sung with pain and his mind felt like it was full of holes, but everything refocused the moment he saw the girl again—sailing up from the ground towards him, her face a blank, emotionless slate mostly obscured by her long bangs, her glinting icy weapon held at the ready. Right before she reached him, the roar of wind parted her bangs and he caught a glimpse of her frozen blue eyes.

They conveyed absolutely no sentiment other than lethal death.

Another flash of blue light.

Then darkness.

* * *

The boy's body hit the pavement, limbs flopping uselessly like those of a rag doll; still, even unconscious, the Keyblade remained in his sturdy grip. The blonde girl landed a second later, standing over the limp boy, the Lion Heart once again slung over her shoulder.

"Wow, you found it! Way to go, Annie!"

Annie turned to find her companion, a ninja who called himself Connie, standing atop the building that she had been on not five minutes ago. Though he wore the same uniform that Annie did, his weapon of choice was a gigantic four-bladed shuriken strapped to his back; the large sheaths strapped to his sides contained an additional plethora of projectile weapons.

Connie dropped down from the building and trotted over to Annie, peering down at the unconscious boy. "This is him? So small."

Annie was aware that the boy with a buzz cut was actually an inch or two taller than she was (which still wasn't saying much), but she quipped anyways, "Says you."

Connie cracked up in laughter. "Ouch! You just made a _burn._ Coming from _you_, it sizzles.**_"_**

Annie didn't reply; she only had eyes for the unconscious boy. "His heart…" she murmured.

"What about his heart?" Connie asked as he crouched down and poked at the Keyblade tentatively.

Annie never responded.

* * *

**_Author's Note_**

_Kingdom Hearts characters replaced by Shingeki no Kyojin people! Really, this entire story started out with **Annie Leonhart = Squall Leonhart**. And the cover photo, drawn by **stevens8** on Pixiv. From there, my imagination ran wild. Though it was originally supposed to be Annie's story (hence the title), I was reminded of the song **Rabbit Heart (Raise It Up) **by **Florence and the Machine**... and that wasn't Annie, so I started writing from Eren's perspective, and then he took over. Yes, this Eren isn't very canon, I know, but he eventually will be underneath Annie's future training and mentoring._

_Or, at least, he would be... but since I'm not expecting a lot of feedback on this story, this is just going to be a two-shot for now. However, when I first sat down and translated my mental inspiration into a computer document, I sketched out a basic outline of plot and characters, including who would be who. I'll include that character list here as a teaser for what would have been. (I decided to have a little fun and gender-swap everybody from Traverse Town/Hollow Bastion, but still keep their general personalities.)_

**Leon** – Annie  
**Yuffie** – Connie  
**Aerith** – Bertholt  
**Cid – **Ymir  
**Sora** – Eren  
**Riku** – Reiner (changed from Jean at reviewer's suggestion)  
**Kairi** – Armin  
**Goofy** – Sasha  
**Donald – **Jean

_Poor Krista, Ymir, Sasha, Jean, Reiner, and Marco: they didn't get to replace anybody. I'm sure I'll find places for them though. One thing's for sure though: if I was ever to write out this entire thing, it certainly wouldn't stick right to the KH plot. Like how Armin's parents and even Eren's parents are withholding secrets already and such. I have a general idea about things._


End file.
